From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx102.postini.com [74.125.245.102]) by kanga.kvack.org (Postfix) with SMTP id 057B86B0002 for ; Fri, 26 Apr 2013 05:55:48 -0400 (EDT) Received: by mail-oa0-f48.google.com with SMTP id f4so3773341oah.35 for ; Fri, 26 Apr 2013 02:55:48 -0700 (PDT) Message-ID: <517A4F1E.9070803@gmail.com> Date: Fri, 26 Apr 2013 17:55:42 +0800 From: Simon Jeons MIME-Version: 1.0 Subject: vmalloc fault Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Linux Memory Management List Cc: Rik van Riel , Dave Hansen , Johannes Weiner , Michal Hocko , Mel Gorman Hi all, 1. Why vmalloc fault need sync user process page table with kernel page table instead of using kernel page table directly? 2. Why do_swap_page doesn't set present flag? 3. When enable DEBUG_PAGEALLOC(catch use-after-free bug), if user process alloc pages from zone_normal(which is direct mapping) when fallback, this page which allocated for user process will set present flag in related pte, correct? but why also set present flag for kernel direct mapping? Does kernel have any requirement to access it? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org